Heat treating apparatus

ABSTRACT

An apparatus for heat treating the cam portion of a camshaft consisting of a shaft portion and a cam portion disposed on the end of the shaft portion generally including a quenching tank, the frame assembly, a carrier assembly partially submersible in a quenching medium disposed in the quenching tank, mounted on the frame assembly for rotation about a longitudinally disposed axis, means disposed on the carrier assembly, circumferentially spaced relative to the axis, for detachably mounting a plurality of camshafts on the carrier assembly, means for rotatably indexing the carrier assembly to position a camshaft mounted on the carrier assembly in a loading and unloading station, a heat treating station and at least one quenching station disposed beneath the surface of a quenching medium disposed in the quenching tank, means disposed on the frame assembly for producing a heated zone of predetermined temperature at the heat treating station, means for extending and retracting the carrier assembly along the longitudinal axis thereof to correspondingly extend into and retract from the heating zone the end portion of the camshaft mounted on the carrier assembly and positioned at the heat treating station, and control means for operating the carrier assembly indexing means and the extending and retracting means.

[45] Oct. 22, 1974 [57] ABSTRACT An apparatus for heat treatin [54] HEAT TREATING APPARATUS g the cam portion of a Cordele, Ga.;

[75] Inventors: Harry Bradshaw,

tracting means.

Attorney, Agent, or Firm-Mason, Fenwickv&

42 Claims, l0 Drawing Figures Lawrence 1 HEAT TREATING APPARATUS This invention relates to a heat treating apparatus and more particularly to an apparatus for heat treating the end'portion of an elongated workpiece. The invention further contemplates a novel apparatus for heat treating the cam portion of a brake camshaft consisting of an elongated shaft portion and a cam portion mounted on the end of the shaft portion.

Conventional non-steering axle assemblies in the prior art generally have consisted of a beam having spindles mounted on the ends thereof, bearings mounted on the spindles, hubs mounted on the spindles, and brake drums mounted on the hubs for rotation therewith. In addition, such assemblies generally have included brake assemblies mounted on the beam adjacent the spindles, cooperable with the brake drums to provide a braking action, brake camshafts operatively connected at their outer ends to the brake assemblies and supported at their inner ends on support brackets mounted on the axle beam, for actuating the brake assemblies, and air chambers mounted on the axle beam having actuating linkages for rotating the brake camshafts to actuate the brake assemblies, including slackv adjusters removably mounted on the inner ends of the brake camshafts by means of spline connections.

In such axle assemblies, the brake assemblies usually include a brake spider mounted on the axle beam and welded or bolted to an annular flange secured to the beam or welded directly to the beam, which is provided at the lower end thereof with a pair of openings for receiving a pair of anchor pins on which the lower ends of the brake shoes are pivotally mounted. The upper ends of such brake spiders are provided with an opening having a bushing in which there is supported the outer end of the brake camshaft.

Brake camshafts of the type utilized in the aforementioned axle assemblies,- generally consist of an elongated shaft supported adjacent its inner end in a bushing of the support bracket and supported adjacent its outer end in the bushing provided in the opening in the upper end of the brake spider. As previously indicated,

the inner end of the shaft is provided with splines on which the slack adjuster is mounted. The outer end of the cam shaft extending beyond the brake spider is provided with an s-shaped cam portion engageable with rollers mounted on the upper ends of the brake shoes. Usually, the brake shoes are provided with interconnecting springs for biasing the shoes together and the rollers thereof into engagement with the surfaces of the s-shaped cam portion so that upon rotation of the brake camshaft, the brake shoes will be moved apart relative to each other to engage the brake drum.

Brake camshafts of the type described usually are fabricated by forging the shaft and cam portions, heat treating the cam portions to provide sufficient hardness of the cam surfaces engageable in wear contact with the rollers ofthe brake shoes, and machining the shaft portions to permit the mounting of the camshafts in the spider and camshaft support brackets, and mounting of the slack adjuster.

ln the past, it generally has been the conventional practice to harden the cam portions of brake camshafts substantially manually by flame hardening and quenching such portions. Such technique, however, has been found not to be entirely satisfactory from the standpoint of efficiency of operation and product quality.

Accordingly, it is the principal object of the present invention to provide an apparatus for mechanically heat treating the cam portions of brake camshoes.

Another object of the present invention is to provide a novel apparatus for mechanically heat treating the cam portions of brake camshafts efficiently at a high production rate.

A further object of the present invention is to provide a novel apparatus for mechanically heat treating and quenching the cam portions of brake camshafts uniformly to consistently provide a desired degree and depth of hardness.

A still further object of the present invention is to provide a novel apparatus for mechanically heat treating and quenching the cam portions of brake camshafts which is comparatively simple in operation, effective in performance and easy to maintain end service.

Other objects and advantages of the present invention will become more apparent to those persons having ordinary skill in the art to which the invention pertains, from the following description taken in conjunction with the accompanying drawings wherein:

FIG. l is a perspective view of an embodiment of the invention; FIG. 2 is a top plan view of the embodiment illustrated in FIG. l.

FIG. 3 is a side elevational view of the embodiment illustrated in FIG. l;

FIG. 4 is an enlarged cross-sectional view taken along line 4-4 in FIG. 3;

FIG. 5 is an enlarged cross-sectional view taken along line 5-5 in FIG. 3;

FIG. 5 is 6 enlarged cross-sectional view taken along line 6-6 in FIG. l;

FIGS. 7 and 8 are perspective views of a positioning device utilized in the embodiment illustrated in FIGS. l through 6;

FIGS. 9A and 9B illustrate a schematic of the control system utilized in the embodiment shown in FIGS. l through 8.

Referring to the drawings, there is illustrated an embodiment of the invention. Generally, the embodiment includes a frame assembly l0, a quenching tank l1 mounted on the frame assembly, a carrier assembly 12 mounted on the frame assembly, an indexing assembly 13 mounted on the frame assembly, an extending and retracting assembly 14 mounted on the frame assembly and operatively connected to the carrier assembly, an induction heating unit 15 mounted on the frame assembly, and a control system 16 for operating the carrier assembly, indexing assembly, extending and retracting assembly and induction heating unit. The frame assembly generally consists of a substantially rectangularly shaped base number 17 supporting at a forward end a housing 18 and a rearward end of housing 19. Quenching tank l1 also is supported on base member 17 between housings 18 and 19.

Forwardly disposed housing 18 includes a forwardly disposed transverse wall 20, a rearwardly disposed transverse wall 2l, a pair of longitudinally disposed walls 22 and 23 and a top wall 24. Rearwardly disposed housing 19 includes a forwardly disposed transverse wall 25, a rearwardly disposed transverse wall 26, a pair of longitudinally disposed side walls 27 and 28 and a top wall 29. As best illustrated in FIG. 3, the level of top walll 29 of housing 19 is below the level of top wall 24 of housing 18. y t v l Quenching tank l1 is adapted to hold any suitable quenching medium'30, usually water, and consists of a forwardly disposed transverse wall 31 disposed adjacent housing wall 21 and'having an inwardly turned top flan'ge3la, a'rearwardly disposed transverse wall 32 disposed adjacent housing wall and having an inwardly turned top flange 32a, a pair of longitudinally disposed side` wallsf33 and 34 disposed in substantial alignment with housing side walls 27 and 28 and having inwardly turned top flanges 33avand 34a, and a transversely inclined-bottom wall 35. Quenching medium is recirculated throughtank l1 and cooled by means of a cooling unit mounted in housing 18 which includes a rec'irculating pump driven by a motor 36. As best illustrated lin FIGS. 2 and 5, the height of the quenching tank is below the level of the top wall of housing 18 and above the top'wall of housing 19.

CARRIER ASSEMBLY bearing member 3 8. Similarly provided in the indexing assembly 13 isa bearing member which registers with thereof priojecting into the housing of index assembly 13. `Tubular'support shaft 41 is disposed above and intermediate the side walls of quenching tank ll. It further is adapted to be rotated about its longitudinal axis but restrained from longitudinal displacement.

Mounted on tubular support shaft 41 and supported on bushings 42 and 43 is a rotatable and longitudinally displaceable tubular shaft 44 having a length substantially less than the spacing between housings 18 and 19. Rigidly mounted on tubular shaft 44 is a forwardly disposed collar member 45 a rearwardly disposed collar member 4 6 and an annular air manifold47 disposed intermediate collars 45 and 46, Supported on collars 45 andv 46 (and the front face of air manifold 47) is a set of trnsvferselydisposed support plates 48, 49 and 50 having substantially "the'same configuration. As best illustrated in FIG. 4, support plate 48 includes radially projecting, circumferentially spaced arm portions 48a, 48b, 48e, and 48d. The arm portions are spaced 90 apart andare disposed in longitudinal alignment with similar arm portions of support plates 49 and 50.

As best shown in FIG. S`, arm portion 48a is provided with a recess 5.1 on which there is secured a set of seating pads 52 and 53. They seating pads are provided with a pair of angularly'disposed'seating surfaces which are disposed in longitudinal alignment with similar seating surfaces on aligned arm portions of support plates 49 and for seating the shaft portion 54 of a camshaft 55 having a cam portion 56 disposed on an end of the shaft portion 54 as illustrated in the drawings and particularly in FIGS. 6 and 7.*lt will be noted that thesets of aligned vseating surfaces permit the mounting oi" four camshafts on the carrier assembly at mounting stations spaced 90 apart. y y

The shaft portions of a setof camshafts are secured at the mounting stations of ther carrier assembly by clamping mechanisms 54a, 55a, `56a and 57 which are mounted on the carrier assembly between` support plates 48 and 49 and which are substantiallysimilar in construction and operation. Clamping mechanism 54 includes an air cylinder'58 having .a piston 59-connected to a clamping lever 60. The base end of air cylinder 58 is pivotally -mounted on alongitudinally disposed pin 6l having the ends thereof supported on support plates 48 and 49. Similarly, clamping lever 60 is pivotally mounted at a point intermediate its ends on a longitudinally disposed pin 62 also supported at its ends on support plates 48 and 49. The outer end of clamping lever is provided with a wear resistantjelement 63 which is engageable with the shaft portion of a camshaft seated on seating pads 52 and 53 to clamp the camshaft at themounting station of the carrier assembly, and is pivotly connected at the oppositev end thereof to the end of piston 59 by means of a pivot pin 64. Air cylinder 58 is provided with a springefor biasing the piston in the extended position and correspondingly maintaining clamping lever 60 in a clamping position.

Clamping lever 60 is moved to an unclamped position, as illustrated in FIG. 5, by supplying air under pressure to the outer end of air cylinder 58 to correspondingly retract piston 59 against the action of the spring within the cylinder. Air under pressure is supplied to the outer end of the cylinder by means of a fluid line and air isdischarged from the base end of the cylinder by means of a fluid line 66, both of which are connectedto anrair valve 67 mounted on the front face of support plate 48. Air under pressure is supplied to air .valve 67 by means of a fluid line 68 interconnecting the air valve and a passageway 69 in support plate member 49 which communicates with the interior of air manifold 47.

urge clamping lever 60 in the clamping position. Air` valve 67 further isvprovided with a longitudinally disposed actuating plunger 70 which normally is biased in the extended position. to close the air valve and which may be depressed to supply air under pressure from fluid line 68 through line .65 to the outer end of cylinder 58 y vEach of the mounting stations of the carrier assembly is adapted to be cycled between a loading and unloading station, heat treating station and a pair of quenching stations designated by the reference letters A, B, C and D which are disposed substantially apart'toco- Y incide with the angular displacement of the mounting stations. As best seen in FIG. 5; the unloading and loading station A is disposed approximately 45 from the vertical plane passing through the axis of the support shaft.

When the mounting station provided on arm member 48a is positioned at the loading and unloading station, `the actuating plunger 70 will be disposed in longitudinal alignment with the'plunger 72 of a solenoid 73 mounted on top wall 24 of housing 18, as best illustrated in FIG. 3. The solenoid isfprovided with a pair of windings 73a and 73b which may be selectively energized to extend andretract plunger 72 to depress and release outwardly spring biased actuating plunger 70 and correspondingly open and close air valve 67. lt further will be appreciated that aseach'mounting station is positioned at the unloading and loading station the actuating plunger of its associated air valve will be positioned in longitudinal alignment with plunger 72 of solenoid 73 to permit the actuation of the air cylinder and correspondingly unclamp and clamp a camshaft positioned at such work station.

Air manifold 47 includes an annular passageway 74 which communicates with air ports 69, 69a, 69b and 69e` through a plurality of longitudinally disposed passageways 75. Air under pressure is supplied from a source disposed either in housing 18 or exteriorly thereof through a fluid line 76 extending from within housing 18 and projecting into support shaft 4l, a passageway 77 provided in a support block 78 sidably mounted in the support shaft, and a rigid fluid pipe 79 intercommunicating passageway 77 and annular passageway 74 in the manifold. As best illustrated in FIG. 5, the rigid pipe 79 extends through a longitudinal slot 80 in the upper portion of support shaft 41. The fluid line 76 preferably is rigid and is connected at a forward end thereof with the source of air pressure through an appropriate rotary connection.

CAM PosirroNlNG ASSEMBLY Mounted on the frame assembly adjacent the unloading and loading station is an assembly 80 for positioning the cam portion of a camshaft mounted on the carrier assembly so that such cam portion will be presented at the heat treating station to the heat treating unit at the proper orientation. As best illustrated in FIGS. 7 and 8, the assembly includes an L-shaped member 81 provided with a horizontal portion 82 secured to top wall 24'of housing 18 adjacent the rear end thereof and inwardly from side wall 23, and a vertical portion 83 having a rearwardly opening guideway 84. Slidably disposed within guideway 84 is an adjusting block 85, the vertical position of which canbe fixed by means of a pair of bolts 86 engageable with the bottom surface of guideway 84. Projecting rearwardly from sliding block 85 is a stub shaft 86 on which there is mounted a sleeve 87. The position of the sleeve 87 may be adjusted along the length of shaft 86and fixed by means of a set screw 88. Rigidly secured on the end of sleeve 87 and disposed substantially diametrically relative to the axis of stub shaft 86 is a guide block 89 having a diametrically disposed guideway 90. An L-shaped member 91 is mounted on guide block 99, having an elongated portion 92 slideable along guideway 90 and a rearwardly disposed leg portion 93. The position of L-shaped abutment member 91 within guideway 90 may be fixed by means of a pair of set screws 94.

lt will be appreciated that the various components of j the camshaft positioning'assembly may be adjusted so that the engagement of the end of a camshaft mounted on the carrier assembly and disposed at the unloading and loading station with surface 92a of the abutment member, and the engagement of one of the edges of the camv portion of the camshaft with either of surfaces 92b and `92C, will properly orient the cam portion relative to the heat treating unit.

lt will be appreciated that the various components of assembly 80 may be adjusted so that rearwardly facing surface 92a of member 90 may be engaged by the end of a cam portion 56 and either of lsurfaces 92b or 92e may be engaged by an edge of the cam portion to position longitudinally a camshaft mounted on the carrier assembly and disposed at the unloading and loading station, and properly orient the cam portion thereof. In actual practice, to load a camshaft on a mounting station positioned at the unloading and loading station, the operator need only place the shaft portion of a camshaft on a set of longitudinally aligned seating pads, slide the camshaft forwardly so that the front face of the cam portion engages surface 92a of member 91 and rotate the crank shaft until an edge thereof engages a surface 92b or 92e.

To accommodate different size camshafts, guide block 8S can be adjusted along guideway 84, sleeve 87 can .be adjusted along the length of stub shaft 86, guide member 89 may be adjusted angularly relative to the axis of stub shaft 86 and abutment member 91 can be adjusted along the length of guideway 90.

INDEXING ASSEMBLY Indexing assembly 13 may be of any suitable conventional type and generally includes a drive motor mounted in housing 19 and a gear train for transmitting drive from the motor to support shaft 41, which further would include a suitable speed reducer. Upon energization, the indexing assembly is operative to rotatably index support shaft 41 and carrier assembly 12 an increment sufficient to advance each mounting station degrees from one work station to a succeeding work station. Drive is transmitted from support shaft 41 to rotabable and longitudinally displaceable shaft 44 in a manner which later will be described.

EXTENDING AND RETRACTING ASSEMBLY Extending and retracting assembly 14 generally consists of a fluid cylinder 95 mounted at its front end to the rear wall 96 of housing 97 for the indexing assembly, coaxially relative to support shaft 51, and a piston or ram 98 which extends into the rearward end of support shaft-11. As best illustrated in FIG. 6, a fixture 99 is mounted on the forward end of piston 98 which is provided with a pair of radially extending, diametrically aligned arm portions 100 and 101 which extend through diametrically aligned, longitudinally extending slots 102 and 103 in support shaft 41 and are rigidly secured to tubular shaft 44.

It will be appreciated that when fluid under pressure is applied selectively to the ends of fluid cylinder 95, piston 98 will be caused to extend and retract and, correspondingly, by virtue of the rigid connection between arm members 100 and 101 and shaft 44, the carrier assembly also will be caused to be displaced longitudinally to position such assembly in a forwardly disposed position as illustrated by the phantom lines in FIG. 6 and in a rearwardly disposed position as illustrated by solid lines. Since during the extension and retraction of piston 98 arm portions 100 and 101 of fixture 99 will travel along the lengths of slots 102 and 103, the longitudinal motion of piston 98 will not be transmitted to support shaft 4l.

- It further will be seen that when support shaft 4l is rotatably indexed by the indexing assembly, such rotary motion will be transmitted from the support shaft to the carrier assembly through the engagement of the side walls of slots 102 and 103 with arm portions 100 and 101 and through the rigid connection between the arm portions and shaft 44. Accordingly, such arrangement of components permits the support shaft, piston 98 and the carrier assembly to be rotatably indexed as an integral unit, and the piston 98 and carrier assembly to be displaced longitudinally between forwardly and rear wardly disposed positions independently of support shaft 4l. Interference by air pipe 79 in the relative longitudinal vdisplacement of tubular shaft 44 and support shaft 41 'is avoided by means of a longitudinally disposed'slot 80 in support shaft v41 which permits the air pipe-79 to travel with the carrier assembly independent of the support shaft. v a

Thek hydraulic circuitry for operating assembly 14 is of a conventional type including a fluid reservoir, a 'fluid line interconnecting the fluid reservoir and a pump driven bya motor 104, a fluid line interconnectingthe pressure side of the fluid pump and a solenoid actuated diverter valve, a return line interconnecting the diverter valve and the fluid reservoir, and a pair of lines interconnecting the diverter valve and the ends of fluid cylinder 95.

INDUCTION HEATING UNIT Induction heating unit also is substantially conventional in construction and operation and includes an appropriate supply of high frequency electrical current disposed in a housing 104 mounted on frame housing 18. Housing 104 is seated on a transversely movable support plate 105 which in turn'is mounted on a longitudi'nally movable support plate 106, as best illustrated in FIGS. 1 and 6. The position of seating plate 105 may beadjusted transversely along a pair of guide members 107 and 108 vby means of a screw mechanism 109 mountedon'support plate 106, andthe position of support plate 106 may be adjusted longitudinally along a pair of guide vmembers 110 'and `ll1 mounted on top wall`24 of housing 18 by means of a screw mechanism 112 which also is mounted on top wall 24.

Secured to a rearwardly disposed wall 113 of housing 104 is a mounting bracket 114v provided with a vertically disposed guideway 115 having a substantially T- shaped cross-sectional configuration. Mounting bracket 114 supports an inductor support bracket 116 which' includes a vertically disposed section 117 disposed within guideway 115, a rearwardly projecting section 118 and a depending section 119. A cam receiving opening 120 is provided in bracket Section 119 about which the inductor coil is disposed and which definesl the heating zone of the inductor coil. The induc- 'tor mounted in support bracket 116 is provided with suitable electrical supply leads which are connected to the power supply disposed within housing 104.

To provide the desired heat penetration of the cam portions of a camshaft. being treated on the machine, opening 120 in the inductor support bracket is provided with a substantially elliptical configuration so that when a properly oriented cam portion of a camshaft is inserted in opening 120, the curved roller engaging surfaces of the cam portion will be positioned 1 adjacent the induction. Such proximity of the curved roller engaging surfaces tothe induction coil will provide the desired penetration of heat to ultimately provide the desired hardening and depth of hardening of such surfaces upon quenching.

Under normal circumstances, the mounting of a camshaft on the carrier assembly with use of the positioning assembly will assure thel proper orientation of the cam portion thereof when the camshaft subsequently is positioned at the heat treating station and the cam portion islinserted` in opening 120. lf, however, for some reason the cam portion of a crank shaft positioned at the heat treating station is misaligned relative to opening 120, such misalignment will be detected by a misalignment detection unit 121.'As best illustrated in FIGS. 1 and 5, unit 121 includes an L-shaped support bracket 122 having a depending portion 123 secured to the rearwardly disposed wall 2l of housing 18 and a rearwardly projecting, horizontally disposed portion 124. A vertically disposed pivot post 125 is mounted on horizontal bracket portion 124, on which there is mounted a pivot plate 126.' A detector plate 127 is mounted along the inner edge of plate 126, which when disposed in a substantially transversed position has a substantially elliptically shaped opening 128 aligned with opening the inductor support bracket.

Whenever the cam portion of a camshaft positioned at the heat treating station is properly oriented and the carrier assembly is extended to its forwardly disposed position, such cam portion will pass through opening 128 and be inserted in opening 120 with the curved Vroller engaging surfaces thereof disposed in the proper position relative to the walls of opening 120. However, whenever such cam portion is misaligned relative to opening 120, the extension of the carrier assembly will cause the cam portion to engage detector plate 127 and cause plate 126 to pivot about pivot post 125. Such pivotal movement correspondingly will cause the outer end of plate 126 to actuate a limit switch 129 which will interrupt the operation of the machine, as later will be described. As best shown in FIG. 2, the'actuating element of limit switch 129 is spring biased against pivot plate 126, the pivotal movement of which is restricted bya stop 130.

OPERATION Referring to FIGS. 9A and 9B, in the operation of the embodiment illustrated in FIGS. 1 through 8, when master switch 200 is closed, appropriate voltages are applied to supply circuit 201 for hydraulic pump motor 104, supply circuit 202 for cooling unit motor 36, and

the primaryvwindings of a step-down transformer 203.

Simultaneously, through the secondary windings of transformer 203, a voltage will be applied to an indexing motor control circuit 204, a pump motorcontrol circuit 205 and a power supply control circuit 206. Hydraulic pump motor 104 may then be started by depressing a starting button control panel 207 to close contacts 208 and energize pump motor control relay 209. Energization of relay 209 will operate to close contacts 209a, 209b and 209C in supply circuit 201 correspondingly to energize pump motor 104, and to close contact 209d in holding circuit 210 connected in parallel across contacts 208 to maintain relay 209 energized. Energization of control circuit 205 also will operate to apply a voltage to motor control circuit 211. To start cooling unit motor 36, a start button also located on control panel 207 is depressed to close contacts 212 and energize motor control relay 213. Energizaton of relay 213 operates to close contacts 213a, 213b and motor 36, and to close contact 213d in holding circuit 214 connected in parallel across contacts 212. The operation of hydraulic pump motor 104 and cooling unit motor 36 functions to supply fluid under pressure to the hydraulic circuit for the extension and retraction assembly 14, cool the coils of the power supply for induction heating unit and circulate quenching medium in tank ll.

Once vcooling unit motor 36 and hydraulic pump motor 104 are operating, the carrier assembly is disposed in its forwardly disposed position and a mounting station thereof is positioned at the unloading and loading work station, the machine may be operated automatically by depressing a power on button to close contacts 215 in power supply control circuit 206, and switching master control switch 216 to the automatic setting. Energizaton of relay 217 in power supply control circuit 206 operates to close a pair of contacts 2l7a and 217b connected in parallel in indexing motor supply circuit 204, contact 217tto apply a voltage to misalignment control circuit 218, and contact 2l7d provided in a holding circuit 219 connected in parallel across contacts 215 to maintain control circuit 206 energized after thepower on button is released and contacts 215 are opened. To begin the automatic cycling of the machine, a start cycle button is depressed to close contacts 220 in cycle control circuit 221 and energize cycle control relay 223. Energizaton of relay 223 operates to close contacts 223a which functions to apply voltages to a cycle supply circuit 224 and a supply circuit 225 for a clamp control timer 226, and close a contact 223b provided in a hold circuit 227a connected in parallel across contacts 220 to maintain relay 223 energized after the start cycle button has been released and contacts 220 are opened. Energizaton of cycle supply circuit 224 further will operate to apply a voltage to carrier retraction supply circuit 227, carrier extension supply circuitv228, carrier retraction control circuit 229, workpiece detection control circuit 230, index timer supplycircuit 231 and index relay control circuit 232.

Again assuming a mounting station is positioned at the unloading and loading station and the carrier assembly is located in its forwardly disposed position, a contact element 233 mounted on air supply conduit 76 will actuate a microswitch 234 which correspondingly will operate to close normally open contacts 234a in clamping timer supply circuit 225 and open normally closed contacts 234b in index timer control circuit 231. Under such conditions, clamp control timer 226 and a heating delay control timer 235 through supply line 236 will be energized, voltages will be applied to supply circuit 237 for unclamping windings 73a and supply circuit 238 for clamping windings 73b of a solenoid 73, and index timer relay 239 .in control circuit 231 and index .relay 240 in control circuit 232 will be deenergized. Simultaneously, voltages will be applied to heating timer supply circuit 241.

Energizaton of timer 226 operates instantly to close contacts 243 in supply circuit 237 to energize windings 73a of solenoid 73 thus causing plunger 72 to extend and depress actuating plunger 70 of valve 67. Such ac- 213C in power supply circuit 202 to energize cooling tion correspondingly will cause fluid under pressure to flow through fluid line to cylinder 58 and retract piston 59 to move clamping lever 60 to an unclamped position as illustrated in FIG. 5. With the clamping lever in the unclamped position, the operator then may mount a camshaft on the carrier assembly by resting the shaft portion thereof on the aligned seating surfaces of seating elements 52 and 53, sliding the crank shaftl forwardly until the cam portion thereof engages surface 92a of abutment member 91, and rotating the camshaft until an edge thereof engages surface 92b of the abutment member. With the camshaft thus positioned, the cam portion thereof will be positioned in the proper orientation to be inserted through opening 128 of detection plate 127 into opening 120 of the inductor support bracket when the camshaft is indexed to the heat treating station.

At the end of a predetermined period of time sufficient to permit an operator to remove a cam shaft mounted on the carrier assembly of the unloading and loading station, and mount and properly position another camshaft at such station timer 226 operates to open contacts 244 and close contacts 245 to deenergize winding 73a and energize windings 73b of solenoid 73 thus causing plunger 72 thereof to retract. Under such circumstances, actuating plunger will extend to permit fluid at the outer end of cylinder 58 to flow through fluid lines 65 and valve 67, and piston 59 to be extended under the force of the spring provided in cylinder 58. Clamping lever 60 then will rotate to engage and clamp the camshaft in position.

Simultaneously with the energization of timer 226, timer 235v will be energized. After a predetermined -time delay sufficient to permit the operator assembly to retract, index an increment and then extend, time 235 will operate to close contacts 246 provided in heating timer supply circuit 247 to energize timer 248. Assuming a camshaft is positioned at the heat treating station, an inductor power supply control relay 249 provided in control circuit 242 will be energized to energize the inductor and correspondingly heat the cam portion of a cam shaft positioned in the inductor support bracket.

Referring to FIGS. 2 and 5, the presence of cam-shaft at the heat treating station is detected by a contact arm 250 which is adapted to be tripped by the cam portion -of a cam-shaft mounted on the carrier assembly while being indexed from the unloading and loading station to the heat treating station. The tripping of contact arm 250 functions to operate a microswitch 251 suported on a bracket 252 secured on housing 18, to close contacts 253 in control circuit 230 and thus energize a control relay 254. Energizaton of control relay 254 operates to close contacts 255 in control circuit 242 and contacts 256 in a holding circuit 257 connected in parallel across contacts 253. Holding circuit 257 will operate to maintain control circuit 230 energized after contact arm 250 has been tripped causing contacts 253 to reopen.

Energizaton of timer 248 will operate to close contacts 258 provided in holding circuit 259 connected in parallel across contacts 246 to maintain timer 258 energized after contacts 246 have opened, open contacts 260 in supply circuit 237, open contacts 261 in control circuit 242 after a predetermined period of time sufficient to heat a cam portion position within opening of inductor support bracket 118, to decontrol circuit 229 after a predetermined time delay.

Assuming the mounting stations of the carrier assembly` are positioned at the work stations, the closing of contacts 262 will energize control relay 263 in control circuit 229. As best illustrated in FIGS. l through 3, the positioning of the mounting stations of the carrier assembly at the work stations of the machine is sensed by a contact arm 264 of a micro-switch 256 supported on a bracket 266 mounted on top wall 29 of housing 19. Contact arm 264 is adapted to be tripped by an actuating pin 267 disposed eccentrically on the enlarged end 268 of a shaft 270. Shaft 270 is operatively connected to the indexing assembly. It is adapted to make a complete rotationcorresponding to the indexing of the carrier assembly an increment of 90 from one work station to another so that when the mounting stations of the carrier assembly are positioned at the work stations of the machine, actuating pin 267 will engage and trip contact arm 264 to actuate micro-switch 256. Whenever micro-switch 265 is actuated, it will operate to close contacts 271 in control circuit 229 and contacts 272 in circuit 273. With contacts 262 and 271 of control circuit 229 closed, control relay 263 will operate to yclose 'contacts' 273 in supply circuit 227, close contacts 274 in holding circuit 276 and open contacts 275 "in control circuit 230. Under such conditions, winding 276a of the solenoid operating'the diverter valve in the hydraulic circuit for cylinder 95 will be energized and operate to divert fluid under pressure to the frontend of cylinder 95 to cause the carrier assembly to be retracted to its rearwardly disposed position.

When the carrier assembly reaches its rearwardly disposed position as illustrated in FIG. 6, an actuating element277 mounted on air supply conduit 76 will engage land close'the contact arm of a micro-switch 278 and correspondingly open contacts 278a in control circuit 229, close contacts 278b in control circuit 231 and close contacts 278e` in a control circuit 279. The opening of contacts 278a` will operateto de-energize control relay 263 and thus prevent any further retraction of the carrier assembly; The closing of contacts 278b will en- 1 ergize control relays 239 and 240 which then will operate to close contacts 239a in supply circuit 228 after a time delay sufficient to index the carrier assembly, open contacts 293b provided in a circuit 280 connected in parallel across contacts 278C, after a predetermined time delay sufficient toV permit the indexing of the carrier assembly, close contacts 240a in circuit 280 and close contacts 240b in a holding circuit 281 connected in parallel across contacts 278b in control circuit 231 to maintaincontrol relays 239 and 240 energized in the event contact 278b may beopened.

n stations.

Referring to FIG. 4, as soon as the carrier assembly has been yindexed a full increment, an actuating element 285 mounted on an annular flange 286 secured to and rotatable with tubular support shaft 41 will engage and trip a contact arm 287 of a micro-switch 288 supported on a bracket 289 mounted on housing 19.

The actuation of micro-switch 288 will then function to open contacts 288a to break holding circuit 283 and close contacts 288b in supply circuit 228. After a predetermined tmedelay as previously indicated, control relay 239 will open contacts 239b to de-energize control relay 282 and the motor for the indexing assembly, and close contacts 239a to energize windings 276b of the solenoid operating the diverter valve in the the hydraulic circuit for cylinder 95. Energization of winding 276b will shift the diverter valve in the hydraulic circuit to supply fluid under pressure to the rear end of cylinder to extend the carrier assembly to its forwardly disposed position. Assuming the cam portion of the camshaft positioned at the heating treating station is properly oriented, such head portion will pass through opening 128 of detection plate 127 and be inserted in opening of the inductor support bracket while the inductor is energized to heat the surfaces of the cam portion.

In the event the cam portion of the camshaft is misaligned relative to opening 128, aslthe carrier assembly is extended to its forwardly disposed position, the cam portion will strike detection plate l27'and cause it to pivot about pivot post 125. Such pivotal action will cause plate 126 to actuate microswitch 129. Actuation of switch 129 will then operate to close contacts 129a in control circuit 218 to energize a control relay 290. Simultaneously, control relay 290 will function to open contacts 290a, close contacts 290b in a holding circuit 291 connected in parallel across contacts 129a and open contacts 290e` in control circuit 221 to stop the cycling of the carrier assembly.

With the master selection switch set for automatic operation, unless the cycle is interrupted because of a misaligned camshaft, the carrier assembly will continue to cycle and index each camshaft successively from the unloading and loading station, to the heat treating and quenching stations and back to the unloading and loading station. By proper setting of the master selector switch 216 the machinev may be operated semiautomatically to cause the carrier assembly to stop at the end of each cycle thus requiring the operator to depress` the start cycle button to begin each new cycle of the carrier assembly. In addition, the master selector switch may be setfor manual operation whereupon the operator would be required to depress various buttons on the control panel to open contacts 292 and 293 in supply circuit 237.*to unclamp and clamp the camshafts at the unloading and loading station, open contacts 294 and 295 iny supply circuit 227 to retract and extend the carrier assembly, and close contacts 296 in control circuit 279 to index the carrier assembly.

The entire control system can be de-energized merely by depressing an emergency stop button to open contacts 297 and brake control circuit 205. Similarly, a stop button may be depressed to open contacts 298 in control circuit 205 and de-energize hudraulic pump motor 104 and cooling unit motor 36, a stop button may be depressed to open contacts 299 in control circuit 211 and de-energize cooling unit motor 36 alone, and a stop cycle button may be depressed to open contacts 300 in control circuit 221 to interrupt the cycling of the carrier assembly.

When the carrier assembly is positioned in its rearwardly disposed position and is indexed to advance a camshaft from the heat treating station to the first quenching station, under normal conditions the heated cam portion of the camshaft upon contacting and entering the quenching medium will develop a gas pocket or void due to the evaporationof the quenching medium. The formation of such a gas pocket impairs the heat transfer between the heated camshaft and the quenching medium and thus results in non-uniform and/or ineffective quenching of the cam portion. To avoid the formation of such a gas pocket or void at the region where the heated cam portion enters the quenching medium, and the attendant undesirable effects, the region'where the heated cam portion enters the quenching medium is agitated which results in the dispersement of the gas formation. Such a agitation is provided by a nozzle 301 which directs a spray of quenching medium supplied through a conduit 302, constantly at the entrant region of a heated camshaft.

From the foregoing detailed description, it will be evident that there are a number of changes, adaptations and modifications of the present invention which come within the province of those skilled in the art. However, it is intended that all such variations not departed from the spirit of the invention be considered as within the scope thereof as limited solely by the appended claims.

We claim:

l. An apparatus for heat treating an end portion of lan elongated workpiece comprising a quenching tank, a frame assembly, a carrier assembly partially submer isible in a quenching medium disposed in said quenching tank, mounted on said frame assembly for rotation about a longitudinally disposed axis, means disposed on v said carrier assembly, circumferentially spaced relative to said axis, for detachably mounting a plurality of said elongatedworkpieces on said carrier assembly, means for rotatably indexing said carrier assembly to position an elongated workpiece mounted in one of said detachably mounting means of said carrier assembly in a loading and unloading station, a heat treating station and at least one quenching station disposed beneath the surface of a quenching medium disposed in said quenching tank, means disposed on said frame assembly for producing a heated zone of predetermined temperature at said heat treating station, means for extending and retracting said carrier assembly along the longitudinal axis thereof to correspondingly extend into and retract from said heating zone the end portion of an elongated workpiecemounted on said carrier assembly and positioned at said heat treating station, and control means for operating said carrierassembly indexing means and said extending andretracting means.

2. An apparatus according to claim 1 including means mounted on said frame assembly for positioning in a predeterminedorientation the end portion of an enlongated workpiece mounted on said carrier assembly ats'aid loading and loading station.

3. An apparatus according to claim 2 wherein said positioning means includes a device provided with abutment surfaces engageable by said end portion.

4. An apparatus according to claim l including means for recirculating said quenching medium through said quenching tank.

5. An apparatus according to claim 4 including means for cooling said quenching medium.

6. An apparatus according to claim 1 including means for preventing the formation of a void in the surface of sa'id quenching medium caused by the gas generated when the heated end portion of an elongated workpiece enters said quenching medium upon being indexed from said heat treating station to said quenching station.

7. An apparatus according to claim 6 wherein said void preventing means comprises means for agitating said region of quenching medium.

8. An apparatus according to claim 6 wherein said void preventing means comprises means for injecting quenching medium under pressure into said region of the quenching medium.

9. An apparatus according to claim 8 wherein said quenching medium projecting means comprises a spray nozzle connected to a supply of quenching medium under pressure.

10. An apparatus according to claim 1 wherein each of said detachably mounting means comprises clamping means and said control means includes means for operating said clamping means when positioned at said loading and unloading station.

11. An apparatus according tovclaim 1 wherein said indexing means includes a motor mounted on said frame assembly and means for transmitting drive from said motor to said carrier assembly, and said control means includes means for periodically actuating said motor for a predetermined period of time to sequentially position each of said detachably mounting means at said heat treating station.

12. An apparatus according to claim 1 wherein said means for producing a heated zone vincludes an induction heating means.

13. An apparatus according to claim 12 wherein said induction heating means includes an induction coil deining therein said heated zone.

14. An apparatus according to claim l wherein said means for extending and retracting said carrier assembly includes a fluid actuated piston and cylinder assembly having the cylinder thereof mounted on said frame assembly and the piston thereof operatively connected to said carrier assembly, and said carrier assembly includes means for selectively supplying fluid under pressure to the ends of said cylinder.

15. An apparatus according to claim l wherein said indexing means includes a motor mounted on said frame assembly and means for transmitting drive from said motor to said carrier assembly, said means for producing a heated zone includes an induction heating means, said means for extending and retracting said carrier assembly includes a fluid actuated piston and cylinder assembly having the cylinder thereof mounted on said frame assembly and the piston thereof operatively connected to said carrier assembly, and said control means includes means for periodically actuating said indexing motor for a predetermined period of time to sequentially position each of said detachably mounting means at said heat treating station, and means for selectively supplying fluid under pressure to the ends of said cylinder.

16. An apparatus according to claim 15 wherein said induction heating means'includes an induction coil defming therein said heated zone.

- 17. An apparatus according to claim 1 wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means includes means responsive to the presence of said carrier assembly in its extended position for moving saidclamping means positioned at said loading and unloading station, into an unclampingposition for a predetermined time to permit the un-loading and loading of said elongated workpieces.

18. An apparatus according to `claim l wherein said control means includes means responsive to the presence of one of said elongated members at said heat treating station and said carrier assembly in its extended position for activating for a predetermined period of time said means for producing a heated zone, after a predetermined time delay commencing from the time said carrier assembly is in the extended position.

An' apparatus according to claim l wherein said control means includes means responsive to a predetermined time delay from the time said carrier assembly i's disposed in its extended position and the presence of said detachably mounting means at said work stations for actuating said means for extending and retracting said carrier assembly, to retract said carrier assembly. 4

20. An apparatus-according to claim l wherein said control means includes means responsive to the presence of said carrier assembly in itsretracted position for indexing said carrier assembly to vcorrespondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations. s

2l. An apparatus according to claim l wherein said control means includes means responsive to the indexing of said carrier assembly from one of said work stations tol a succeeding one of said work stations for extending said carrier assembly at the end of an indexing increment. y'

2,2.An apparatus according to vclaim Vl wherein said control means includes means responsive to a misalignm'ent of the end portion of an elongated workpiece positioned at said heat treating station, relative to said heated zone for preventing the extensionof said carrier assembly and correspondinglythe insertion of said end portion into said heated zone.

23. An apparatus according to claim l wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means `includes means responsive to the presence of said carrier assembly in its extended position and Y said vclamping means positioned at said loading and unvating for a predetermined period of time said means for producing a heated zone, after a predetermined time delay commencing from the time said carrier assembly is in the extended position, means responsive to a predetermined time delay commencing from the time said carrier assembly is disposed in its extended posi-l tion and the presence of said detachably mounting means at said work stations for actuating said means for extending and retracting said carrier assembly to retract said carrier assembly, means `responsive to the presence of said carrier assembly in its retracted position forindexing said carrier assembly to correspondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations, means responsive to the indexing of such carrier assembly from one of said work stations to a succeeding one of said work stations 4for extending said carrier assembly at the end of an` indexing increment, and means responsive to a misalignment of the end portion of an elongated workpiece positioned at said heat treating station, relative to saidheated zone, for preventing the extension of said carrier assembly and correspondingly the insertion of said end portion into said heated zone.

24. An apparatus for surface hardening the cam portion of a camshaft consisting of a shaftvportion .and a cam portion disposed on an encl of said shaft portion comprising a tank for holding a quenching medium', a

longitudinally disposed, tubular support shaft mounted on said frame assembly for rotation about its axis, a second tubular shaft coaxially mounted on said support shaft, a carrier assembly mounted on said second tubular shaft, means disposed on said carrier assembly, circumferentially spaced relative to said axis, for detachably'mounting a plurality of camshafts on said carrier assembly with the cam portions thereof disposed forwardly, a fludactuated piston and cylinder assembly mounted on said frame assembly and disposedcoaxially relative to said tubular shafts, said fluid actuated piston and cylinder assembly including a cylinder rigidly mounted on said frame assembly and a piston extending into said tubular support shaft, said tubular supportshaft having at least one longitudinally disposed slot, said piston having a radially disposed member extending through said slot and secured to said second shaft whereby upon extending and retracting said piston, said second shaft will be caused to be displaced longitudinally relative to said support shaft to position said carrier assembly selectively at lforwardly and rearwardly disposed positions and upon rotating said support shaft the'sides of said slot will engage said radially disposed member to rotate said tubular shafts in unison, means for rotatably indexing said support shaft and correspondingly said carrier assembly to position a camshaft mounted in one-of said detachably mount-v ing means of said carrier assembly in a loading and unloading station, a heat treating station and at least one quenching station disposed beneath ,the surface of quenching medium disposed in said quenching tank, l means disposed on said frame assembly for producing v in a predetermined orientation the cam portion of a` camshaft mounted on said carrier assembly at said loading and unloading station.

26. An apparatus according to claim 25 wherein said positioning means includes a device provided with abutment surfaces engageable by said cam portion.

27. A'n apparatus according to claim 24 including means for recirculating said quenching medium through said quenching tank.

28. An apparatus according to claim 26 including means for cooling said quenching medium.

29. An apparatus according to claim 24 including means for preventing the formation of a void in the surface of said quenching medium caused by the gas generated when the heated cam portion of a camshaft enters the quenching medium upon being indexed from said heat treating station to said quenching station.

30. An apparatus according to claim 29 wherein said void preventing means comprises means for agitating said region of quenching medium.

31. An apparatus according to claim 29 wherein said void preventing means comprises means for injecting quenching medium under pressure into said region of the quenching medium.

32. An apparatus according to` claim 31 wherein said quenching medium injecting means comprises a spray nozzle connected to a supply of quenching medium under pressure. v

33. An apparatus according to claim 24 wherein each of said detachably mounting means comprises clamping means and said control means includes means for operating said clamping means when positioned at said loading and unloading station.

34. An apparatus according to claim 24 wherein said means for producing a heated zone includes an induction heating means.

35. An apparatus according to claim 34 wherein said induction heating means includesaninduction coil defining therein said heating zone.

36. An apparatus according to claim 24 wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means includes means responsive to the presence of said carrier assembly in its extended position for moving said clamping means positioned at said loading and unloading station, into an unclamped position for a predetermined time to permit the unloading and loading of said elongated members. l

37. An apparatus according to claim 24 wherein said control means includes means responsive to the presence of one of said elongated workpieces at said heat treating station and said carrier assembly in its extended position for activating for a predetermined period` of time said means for producing a heated zone, after a-predetermined time delay commencing from the time said carrier assembly is in the extended position.

38. An apparatus according to claim 24 wherein said control means includes means responsive to a predetermined time delay from the time said carrier assembly is disposed in its forward position and the presence of said detachably mounting means at said work stations for actuatingsaid means for extending and retracting said carrier assembly, to retract said carrier assembly to its rearwardly disposed position.

39. An apparatus according to claim 24 wherein said control means includes means responsive to the presence of said carrier assembly in its rearwardly disposed position for indexing said carrier assembly to correspondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations.

40. An apparatus according to claim 24 wherein said control means includes means responsive to the indexing of said carrier assembly from one of said work stations to a succeeding one of said work stations for extending said carrier assembly from its rearwardly disposed position to its forwardly disposed position at the end of an indexing increment.

4l. An apparatus according to claim 24 wherein said control mounting includes means responsive to misalignment ofthe cam portion of a camshaft positioned at said heat treating station, relative to said heating zone for preventing the travel of said carrier assembly to its forwardly disposed position and correspondingly the insertion of said cam portion into said heating zone.

42. An apparatus according to claim 24 wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means includes means responsive to the presence of said carrier assembly in its forwardly disposed position for moving said clamping means positioned at said loading and unloading station, into an unclamping posi tion for a predetermined time to permit the unloading and loading of one of said camshafts, means responsive to the presence of one of said camshafts at said heat treating station and said carrier assembly in its forwardly disposed position for activating for a predetermined period of time said means for producing a heated zone, after a predetermined time delay commencing from the time said carrier assembly is in the extended position, means responsive to a predetermined time delay from the time said carrier assembly is disposed in its forwardly disposed position and the presence of said detachably mounting means at said work stations for actuating said fluid actuated piston and cylinder assembly, to retract said carrier assembly to its rearwardly disposed position, means responsive to the presence of said carrier assembly in its rearwardly disposed position for indexing said carrier assembly to correspondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations, means responsive to the indexing of said carrier assembly from one of said work stations for extending said carrier assembly to its forwardly disposed position at the end of an indexing increment, and means responsive to a misalignment of the cam portion of a camshaft positioned at said heat treating station, relative tosaid heated zone for preventing the extension of said carrier assembly to its forwardly disposed position and correspondingly the insertion of said cam portion into said heated zone.

l= l= l =l 

1. An apparatus for heat treating an end portion of an elongated workpiece comprising a quenching tank, a frame assembly, a carrier assembly partially submerisible in a quenching medium disposed in said quenching tank, mounted on said frame assembly for rotation about a longitudinally disposed axis, means disposed on said carrier assembly, circumferentially spaced relative to said axis, for detachably mounting a plurality of said elongated workpieces on said carrier assembly, means for rotatably indexing said carrier assembly to position an elongated workpiece mounted in one of said detachably mounting means of said carrier assembly in a loading and unloading station, a heat treating station and at least one quenching station disposed beneath the surface of a quenching medium disposed in said quenching tank, means disposed on said frame assembly for producing a heated zone of predetermined temperature at said heat treating station, means for extending and retracting said carrier assembly along the longitudinal axis thereof to correspondingly extend into and retract from said heating zone the end portion of an elongated workpiece mounted on said carrier assembly and positioned at said heat treating station, and control means for operating said carrier assembly indexing means and said extending and retracting means.
 2. An apparatus according to claim 1 including means mounted on said frame assembly for positioning in a predetermined orientation the end portion of an enlongated workpiece mounted on said carrier assembly at said loading and loading station.
 3. An apparatus according to claim 2 wherein said positioning means includes a device provided with abutment surfaces engageable by said end portion.
 4. An apparatus according to claim 1 including means for recirculating said quenching medium through said quenching tank.
 5. An apparatus according to claim 4 including means for cooling said quenching medium.
 6. An apparatus according to claim 1 including means for preventing the formation of a void in the surface of said quenching medium caused by the gas generated when the heated end portion of an elongated workpiece enters said quenching medium upon being indexed from said heat treating station to said quenching station.
 7. An apparatus according to claim 6 wherein said void preventing means comprises means for agitating said region of quenching medium.
 8. An apparatus according to claim 6 wherein said void preventing means comprises means for injecting quenching medium under pressure into said region of the quenching medium.
 9. An apparatus according to claim 8 wherein said quenching medium projecting means comprises a spray nozzle connected to a supply of quenching medium under pressure.
 10. An apparatus according to claim 1 wherein each of said detachably mounting means comprises clamping means and said control means includes means for operating said clamping means when positioned at said loading and unloading station.
 11. An apparatus according to claim 1 wherein said indexing means includes a motor mounted oN said frame assembly and means for transmitting drive from said motor to said carrier assembly, and said control means includes means for periodically actuating said motor for a predetermined period of time to sequentially position each of said detachably mounting means at said heat treating station.
 12. An apparatus according to claim 1 wherein said means for producing a heated zone includes an induction heating means.
 13. An apparatus according to claim 12 wherein said induction heating means includes an induction coil defining therein said heated zone.
 14. An apparatus according to claim 1 wherein said means for extending and retracting said carrier assembly includes a fluid actuated piston and cylinder assembly having the cylinder thereof mounted on said frame assembly and the piston thereof operatively connected to said carrier assembly, and said carrier assembly includes means for selectively supplying fluid under pressure to the ends of said cylinder.
 15. An apparatus according to claim 1 wherein said indexing means includes a motor mounted on said frame assembly and means for transmitting drive from said motor to said carrier assembly, said means for producing a heated zone includes an induction heating means, said means for extending and retracting said carrier assembly includes a fluid actuated piston and cylinder assembly having the cylinder thereof mounted on said frame assembly and the piston thereof operatively connected to said carrier assembly, and said control means includes means for periodically actuating said indexing motor for a predetermined period of time to sequentially position each of said detachably mounting means at said heat treating station, and means for selectively supplying fluid under pressure to the ends of said cylinder.
 16. An apparatus according to claim 15 wherein said induction heating means includes an induction coil defining therein said heated zone.
 17. An apparatus according to claim 1 wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means includes means responsive to the presence of said carrier assembly in its extended position for moving said clamping means positioned at said loading and unloading station, into an unclamping position for a predetermined time to permit the un-loading and loading of said elongated workpieces.
 18. An apparatus according to claim 1 wherein said control means includes means responsive to the presence of one of said elongated members at said heat treating station and said carrier assembly in its extended position for activating for a predetermined period of time said means for producing a heated zone, after a predetermined time delay commencing from the time said carrier assembly is in the extended position.
 19. An apparatus according to claim 1 wherein said control means includes means responsive to a pre-determined time delay from the time said carrier assembly is disposed in its extended position and the presence of said detachably mounting means at said work stations for actuating said means for extending and retracting said carrier assembly, to retract said carrier assembly.
 20. An apparatus according to claim 1 wherein said control means includes means responsive to the presence of said carrier assembly in its retracted position for indexing said carrier assembly to correspondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations.
 21. An apparatus according to claim 1 wherein said control means includes means responsive to the indexing of said carrier assembly from one of said work stations to a succeeding one of said work stations for extending said carrier assembly at the end of an indexing increment.
 22. An apparatus according to claim 1 wherein said control means includes means responsive to a misalignment of the end portion of an elongated workpiece positioned at said heat treating station, relative to said heated zone For preventing the extension of said carrier assembly and correspondingly the insertion of said end portion into said heated zone.
 23. An apparatus according to claim 1 wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means includes means responsive to the presence of said carrier assembly in its extended position and said clamping means positioned at said loading and unloading station for moving said clamping means into an unclamping position for a predetermined time to permit the unloading and loading of said elongated members, means responsive to the presence of one of said elongated workpieces at said heat treating station and said carrier assembly in its extended position for activating for a predetermined period of time said means for producing a heated zone, after a predetermined time delay commencing from the time said carrier assembly is in the extended position, means responsive to a predetermined time delay commencing from the time said carrier assembly is disposed in its extended position and the presence of said detachably mounting means at said work stations for actuating said means for extending and retracting said carrier assembly to retract said carrier assembly, means responsive to the presence of said carrier assembly in its retracted position for indexing said carrier assembly to correspondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations, means responsive to the indexing of such carrier assembly from one of said work stations to a succeeding one of said work stations for extending said carrier assembly at the end of an indexing increment, and means responsive to a misalignment of the end portion of an elongated workpiece positioned at said heat treating station, relative to said heated zone, for preventing the extension of said carrier assembly and correspondingly the insertion of said end portion into said heated zone.
 24. An apparatus for surface hardening the cam portion of a camshaft consisting of a shaft portion and a cam portion disposed on an end of said shaft portion comprising a tank for holding a quenching medium, a longitudinally disposed, tubular support shaft mounted on said frame assembly for rotation about its axis, a second tubular shaft coaxially mounted on said support shaft, a carrier assembly mounted on said second tubular shaft, means disposed on said carrier assembly, circumferentially spaced relative to said axis, for detachably mounting a plurality of camshafts on said carrier assembly with the cam portions thereof disposed forwardly, a fluid actuated piston and cylinder assembly mounted on said frame assembly and disposed coaxially relative to said tubular shafts, said fluid actuated piston and cylinder assembly including a cylinder rigidly mounted on said frame assembly and a piston extending into said tubular support shaft, said tubular support shaft having at least one longitudinally disposed slot, said piston having a radially disposed member extending through said slot and secured to said second shaft whereby upon extending and retracting said piston, said second shaft will be caused to be displaced longitudinally relative to said support shaft to position said carrier assembly selectively at forwardly and rearwardly disposed positions and upon rotating said support shaft the sides of said slot will engage said radially disposed member to rotate said tubular shafts in unison, means for rotatably indexing said support shaft and correspondingly said carrier assembly to position a camshaft mounted in one of said detachably mounting means of said carrier assembly in a loading and unloading station, a heat treating station and at least one quenching station disposed beneath the surface of quenching medium disposed in said quenching tank, means disposed on said frame assembly for producing a heated zone of predetermined temperature at a location for receiving therein the cam portion of a cAm shaft disposed in a detachably mounting means positioned at said heat treating station when said carrier assembly is disposed at its forwardly disposed position, and control means for operating said indexing means and said fluid actuated piston and cylinder assembly.
 25. An apparatus according to claim 24 including means mounted on said frame assembly for positioning in a predetermined orientation the cam portion of a camshaft mounted on said carrier assembly at said loading and unloading station.
 26. An apparatus according to claim 25 wherein said positioning means includes a device provided with abutment surfaces engageable by said cam portion.
 27. An apparatus according to claim 24 including means for recirculating said quenching medium through said quenching tank.
 28. An apparatus according to claim 26 including means for cooling said quenching medium.
 29. An apparatus according to claim 24 including means for preventing the formation of a void in the surface of said quenching medium caused by the gas generated when the heated cam portion of a camshaft enters the quenching medium upon being indexed from said heat treating station to said quenching station.
 30. An apparatus according to claim 29 wherein said void preventing means comprises means for agitating said region of quenching medium.
 31. An apparatus according to claim 29 wherein said void preventing means comprises means for injecting quenching medium under pressure into said region of the quenching medium.
 32. An apparatus according to claim 31 wherein said quenching medium injecting means comprises a spray nozzle connected to a supply of quenching medium under pressure.
 33. An apparatus according to claim 24 wherein each of said detachably mounting means comprises clamping means and said control means includes means for operating said clamping means when positioned at said loading and unloading station.
 34. An apparatus according to claim 24 wherein said means for producing a heated zone includes an induction heating means.
 35. An apparatus according to claim 34 wherein said induction heating means includes an induction coil defining therein said heating zone.
 36. An apparatus according to claim 24 wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means includes means responsive to the presence of said carrier assembly in its extended position for moving said clamping means positioned at said loading and unloading station, into an unclamped position for a predetermined time to permit the unloading and loading of said elongated members.
 37. An apparatus according to claim 24 wherein said control means includes means responsive to the presence of one of said elongated workpieces at said heat treating station and said carrier assembly in its extended position for activating for a predetermined period of time said means for producing a heated zone, after a predetermined time delay commencing from the time said carrier assembly is in the extended position.
 38. An apparatus according to claim 24 wherein said control means includes means responsive to a predetermined time delay from the time said carrier assembly is disposed in its forward position and the presence of said detachably mounting means at said work stations for actuating said means for extending and retracting said carrier assembly, to retract said carrier assembly to its rearwardly disposed position.
 39. An apparatus according to claim 24 wherein said control means includes means responsive to the presence of said carrier assembly in its rearwardly disposed position for indexing said carrier assembly to correspondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations.
 40. An apparatus according to claim 24 wherein said control means includes means responsive to the indexing of said carrier assembly from one of said work stations to a succeeding one of said work stations for Extending said carrier assembly from its rearwardly disposed position to its forwardly disposed position at the end of an indexing increment.
 41. An apparatus according to claim 24 wherein said control mounting includes means responsive to misalignment of the cam portion of a camshaft positioned at said heat treating station, relative to said heating zone for preventing the travel of said carrier assembly to its forwardly disposed position and correspondingly the insertion of said cam portion into said heating zone.
 42. An apparatus according to claim 24 wherein said detachably mounting means comprises clamping means normally biased in a clamping position, and said control means includes means responsive to the presence of said carrier assembly in its forwardly disposed position for moving said clamping means positioned at said loading and unloading station, into an unclamping position for a predetermined time to permit the unloading and loading of one of said camshafts, means responsive to the presence of one of said camshafts at said heat treating station and said carrier assembly in its forwardly disposed position for activating for a predetermined period of time said means for producing a heated zone, after a predetermined time delay commencing from the time said carrier assembly is in the extended position, means responsive to a predetermined time delay from the time said carrier assembly is disposed in its forwardly disposed position and the presence of said detachably mounting means at said work stations for actuating said fluid actuated piston and cylinder assembly, to retract said carrier assembly to its rearwardly disposed position, means responsive to the presence of said carrier assembly in its rearwardly disposed position for indexing said carrier assembly to correspondingly index one of said detachably mounting means from one of said work stations to a succeeding one of said work stations, means responsive to the indexing of said carrier assembly from one of said work stations for extending said carrier assembly to its forwardly disposed position at the end of an indexing increment, and means responsive to a misalignment of the cam portion of a camshaft positioned at said heat treating station, relative to said heated zone for preventing the extension of said carrier assembly to its forwardly disposed position and correspondingly the insertion of said cam portion into said heated zone. 